I want to decrease the vertical space between the top of the page and the chapter heading. I have tried to follow the instructions for titlesec but I am not successful. I have tried the following two setups without any changes occuring.

First:

\documentclass[12pt]{report}
\usepackage[compact]{titlesec}
\begin{document}
\chapter{Characters}
The origin of the group determinant begins with Richard Dedekind in the late 1800's. He began to explore the idea after studying the discriminant in a normal field [A]. He made several observations about the group determinant, but was only able to prove some of them.
\end{document}

Second:

\documentclass[12pt]{report}
\usepackage{titlesec}
\titleformat{\chapter}[display]
{\normalfont\huge\bfseries}{\chaptertitlename\ \thechapter}{20pt}{\Huge}
\titlespacing{\chapter}{0pt}{0pt}{0pt}
\begin{document}
\chapter{Characters}
The origin of the group determinant begins with Richard Dedekind in the late 1800's. He began to explore the idea after studying the discriminant in a normal field [A]. He made several observations about the group determinant, but was only able to prove some of them.
\end{document}

1 Answer
1

For many reasons, titlesec continues to use the default \@makechapterhead macro for typesetting the chapter title when the chapter style is display. So

\documentclass[12pt]{report}
\usepackage{titlesec}
\titleformat{\chapter}[display]
{\normalfont\huge\bfseries}{\chaptertitlename\ \thechapter}{20pt}{\Huge}
\titlespacing*{\chapter}{0pt}{-50pt}{40pt}
\begin{document}
\chapter{Characters}
The origin of the group determinant begins with Richard Dedekind in the late 1800's. He began to explore the idea
after studying the discriminant in a normal field [A]. He made several observations about the group determinant, but
was only able to prove some of them.
\end{document}

will do, since \@makechapterhead adds a 50pt space above the title and 40pt after it.

A different strategy might be to redefine \@makechapterhead yourself:

\documentclass[12pt]{report}
\makeatletter
\def\@makechapterhead#1{%
%%%%\vspace*{50\p@}% %%% removed!
{\parindent \z@ \raggedright \normalfont
\ifnum \c@secnumdepth >\m@ne
\huge\bfseries \@chapapp\space \thechapter
\par\nobreak
\vskip 20\p@
\fi
\interlinepenalty\@M
\Huge \bfseries #1\par\nobreak
\vskip 40\p@
}}
\def\@makeschapterhead#1{%
%%%%%\vspace*{50\p@}% %%% removed!
{\parindent \z@ \raggedright
\normalfont
\interlinepenalty\@M
\Huge \bfseries #1\par\nobreak
\vskip 40\p@
}}
\makeatother
\begin{document}
\chapter{Characters}
The origin of the group determinant begins with Richard Dedekind in the late 1800's. He began to explore the idea
after studying the discriminant in a normal field [A]. He made several observations about the group determinant, but
was only able to prove some of them.
\end{document}

The first solution has a bit problem if before the first chapter there's a paragraph. The second solution works, but, is it possible to make the Chapter number and title in the same line?
–
athosMar 10 at 10:19